Safety device for invalids&#39; wheel chairs



Feb. 2, 1954 R. A. CALDEIRA 2,667,945

SAFETY DEVICE FOR INVALIDS WHEEL CHAIRS Filed March 10, 1950v IN VENTOR. v

Rum ACAlDf/KA.

A'TTOKNEY Patented Feb. 2, 1954 UNITED STATES OFFICE SAFETY DEVICE FORINVALIDS WHEED CHAIRS Ruth A. Caldeira, BrooklyrnN; ApplicationMarchll),1950, Serial No. 149,854

6 Claims.

This, invention relates to safety devices for invalid wheel chairs, andmore particularly is directed to braking devices which are easilyattached to existing wheel chairs, and when so attached operate whendesired to lock the wheel chair against forward or backward rollingmovement.

An object of the present invention is to provide a braking device forwheel chairs which is sturdy and simple inconstruction, so as. toprovide for the inexpensive manufacture thereof, and yet is foolproofand effective in its locking operation.

Another object of this invention is to provide a braking device forwheel chairs which with slight modifications may be secured to eitherthe member forming the arm rest of the chair, on either of the sidesthereof, to the member forming the back rest, or to the member fromwhich the foot rest is suspended, the place of" attachment dependingupon the construction of the particular wheel-chair.

A further object is to provide a braking device for wheel chairs whichengages between the spokesof the wheels thereof, when in thebrakingposition, and thereby prevents rotation of the wheel in eitherdirection.

Still another object is to provide a braking device for wheel chairs inwhich the braking element once engaged between the spokes of the wheelis positively retained in the locked position.

A still further object of this invention is to provide a braking devicewhich in one position engages between the spokes of the wheel chairwheels for arresting rotation of the wheel in either direction, and inthe inactive position engages against structural members of the wheelchair so as to be retained in inoperative position.

Other and further objects of the present invention will be apparent fromthe following description and the accompanying drawing;

In accordance with each of the several forms of the invention, theforegoing objects are accomplished by providing a base or'clamp forattachment to one of the several structural members of the wheel chair,and pivotally mounting a suitably curved arm upon the clamp or base insuch manner that the free end of the curved arm will engage between thespokes of the wheel inv one pivoted position of the arm. Furthermore,the free end. of. the arm is provided with suitably formed notches,within which the adjacent spokes of the-wheelengage, whenthe arm is inbraking position, so" as to: preventpivoting of the arm away fromlooking or braking posi- 2. tion. Finally, the pivoted arm is so formed.as to engage against theside surface-of'oneof the structural members ofthe wheel chair, to be held'or retained in inoperative position.

Preferred embodiments of the invention are illustrated in theaccompanying drawing, in which Figure 1 is a side elevational view of awheel chair having a braking'device in accordance with this inventionattached thereto;

Figure 2 is a fragmentaryside elevational view, on an enlarged scale, ofthe wheelchair shown in Figure 1, with the locking, or braking, arm ofthe attached device shown in inoperativeposition in broken'lines';

Figure 3 15a vertical view, looking at; the braking device from therear" of: the wheel chair, with portions of the wheel chair broken away,and with the braking: arm shown in inoperative position in broken lines;

Figure lis a fragmentary side elevation of the wheelchair of Figure land Figure 2, on anenlarged scale, showing the details of constructionof the braking device, ,with the locking armshown in inoperativeposition in broken lines; and

Figure 5 is a fragmentary side elevation of a portion-"of. a modifiedform of the braking device for wheel chairs in accordance with thisinventiOII;

Referring to the drawing indetail, andinitially to Figures l 2, 3 and 4thereof, there-is. shown a wheelchair ID of common construction,. andincluding propellingwheels. H of relatively large diameter, havingradially extending angularly spacedapartspokes l2. Thewheelchair I'llf'urther'includessa'backrestv having side frame members l3,which:extendsubstantially vertically, and arm rest framemembers l4extendingsubstantially in a horizontal direction, and joined at theirvrear ends. to the verticaLframe members 13. The opposite. vertical framemembers l3 and the arm rest frame members [4. are preferably formed ofmetallic tubing in accordance with the modern practice in. wheel chairconstruction.

I he braking device inaccordance with this invention is. generallyindicated byv the numeral 15-, anditsrdetails of construction are bestseen in the enlarged view of Figures 3' and 4. The braking device l5includes a clamp portion l5 and alocking: arm portion. I]. The clamportion it includes a pair. of clamp forming members I! and l-bfor-medpreferably oia metal havinghighstrength characteristics. Themember I 8,- is widest at, its central. portion,, as seen in Figure 4,and tapers towards its opposite ends.

The member I! is straight sided, or may be provided with a similar form,and both of the members I! and I8 are formed with arcuate grooves intheir confronting spaces for reception of the tubular arm rest I4.Counter-sunk bores are formed in the member I8, adjacent each of theopposite ends thereof,-and securing bolts I9 and 28 extend rotatablythrough such bores and are tapped into the member I1. As seen in Figure3, the bolts I9 and are respectively disposed above and below thehorizontal frame member I4 and when tightened clamp the members I! andI8 upon the .opposite sides of that frame member. The member I8 isformed with spaced apart lugs 2| and 22 extending outwardly from thecentral portion thereof, and defining a vertically opening spacetherebetween. As seen in Figure 4, the thickness of the lug 22 issubstantially greater than that of the lug 2 I. A countersunk boreextends horizontally through the lug 22, and a pivot member 23 extendshorizontally through the bore in the lug 22 and is tapped into the lug2!. A nut 24 is threaded upon the end of the pivot member or bolt 23which extends through the lug 2 I.

The locking arm I! is formed of a length of round metallic stock, havingthe sides thereof squared off adjacent one end, as indicated at 25. Abore 26 is formed through that one end of the arm I'!, and opens at itsopposite ends at the flattened surfaces 25. The locking arm I? ispivotally mounted upon the clamp I8 by the pivot member 23 extendingthrough the bore 26 of the arm. A locking washer 2i, and a pair of plainwashers 28 on opposite sides of the locking washer, are interposedbetween the flat surface of the arm I] and the inner surface of therelatively thin lug 2|. Rotation of the pivot member 23, in onedirection relative to the lugs 2| and 22, will effect the springing ofthe thin lug 2i towards the relatively thick lug 22, and will reduce thedistance between the lugs for clamping the washers against the face ofthe locking arm. This structure provides means for varying the drag, orresistance to pivoting, of the arm I'!.

Viewed at right angles to the plane of pivoting, as in Figure 3, the armI! is preferably formed with an outwardly inclined portion 29, which atits lower end extends into the inwardly curved portion 30. The free endof the arm I? is formed with a straight portion 3I extending inwardly,and formed with inclined notches 32 on each of the opposite sidesthereof. The notches 32 are deepest at their end adjacent to the freeextremity of the arm I!, and at these deepest ends are provided withstraight walls 33 extending at right angles to the plane of movement ofthe arm I! about the pivot 23.

The arm I!, when viewed from the outer side, in a plane parallel to theplane of movement about the pivot 23, as shown in Figure 4, is inclinedrearwardly towards the vertical frame member I3, for a purpose to behereinafter set forth. The arm I! is formed with a longitudinallyarcuate recess 34 on the rear side thereof, adjacent the end of thenotch 32 remote from the free extremity of the arm. The arm I1, beingformed of a metallic material, has inherent resilience, and when it isrocked upwardly to the position shown in broken lines in Figures 2, 3and 4, the portions of the arm having the arcuate recess 34 formedtherein will engage against the front surface of the vertical framemember I3. A portion of the vertical frame 4 member I3 will beresiliently received within the recess 34 and such engagement willprevent the inadvertent swinging of the arm from this inoperativeposition.

When it is desired to lock the wheels I I of the wheel chair againstrotation in either direction, the arm I! is rocked downwardly about thepivot 23 into the position shown in full lines in the several views ofthe drawing. In this position, the end 3| of the arm will extend betweenadjacent spokes I2 .of the wheel. Rotation of the wheel in eitherdirection will then cause one or the other of the spokes on oppositesides of the end 3! of the arm to bear against that portion of the arm.When the spoke I2 bears against the portion 3| of the arm, the spokewill be disposed within the notch 32 formed therein, and will preventswinging of the arm out of this locking position, by engaging againstthe right angled wall 33 of the notch 32, as seen in Figure 3. Thespecific construction set forth above provides a braking device forwheel chairs in which the frictional drag acting against pivoting of thearm I! can be adjusted, and in which the arm is retained either ininoperative position, as shown in broken lines in the several figures ofthe drawing, or in operative wheel locking position as seen in fulllines.

In Figure 5, a modified form of the braking device in accordance withthis invention is illustrated, which is adapted to be attached to thevertical frame member I3, rather than to the horizontal frame member I4as set forth in the detailed description of Figures 1, 2, 3 and 4. Inthis modified form, the lugs 25 and 22' extending outwardly from theclamp forming member IS are each disposed in a plane extending at rightangles to a line drawn through the securing bolts I9 and 20'. This is tobe distinguished from the disposition of the lugs 2! and 22 in the firstform of the invention, which lugs are disposed in planes extendingparallel to a line drawn through the clamping bolts I9 and 20. The lugs2! and 22' provide a support for the pivot member 23' which forms asubstantially horizontal pivoting axis for the locking arm -I'!. In themodified form the operation of the braking device is identical with thatset forth above in connection with the first form of the invention, withthe exception that the arm I! continues to engage against the side ofthe vertical member I3 for retention in the inoperative position.

It is understood that the braking device can be adapted to operate onthe left hand wheelof the wheel chair, as distinguished from the arms I!and I!, which are each adapted to lock the right hand wheel of thechair, by reversing the respective parts.

While I have illustrated and described preferred embodiments of myinvention, it is to be understood that I do not wish to be limited tothe precise structure thereof, as obviously various modifications andchanges may be made therein without departing from the spirit and scopeof the invention as defined in the appended claims.

What I claim is:

1. In combination with an invalids wheelchair including spoked wheelsand side frame members; a braking device comprising a clamp mounted onone of said side frame members. a pivot member on said clamp, a lockingarm pivoted at one end on said pivot member and formed with a hookedfree end loosely projecting axially between a pair of spokes on theadjacent one of said wheels in one pivoted operative position of saidarm, means on said clamp frictionally engaging the pivoted end of saidarm and resisting the swinging of the latter, means on said armreceiving a spoke bearing against said arm when the latter is in saidone operative position and resisting pivoting of said arm from said oneposition, and means on said arm engageable with one of said side framemembers when said arm is in another pivoted inoperative positionyieldably retaining said arm in said inoperative position.

2. The combination according to claim 1, wherein said clamp includes apair of spaced outwardly extending lugs, and said pivot member consistsof a headed bolt extending loosely through one of said lugs and tappedinto the other of said lugs, said locking arm being pivoted on said boltbetween said lugs, said one of said lugs being relatively thick and saidother of said lug being relatively thin, and including locking washersinterposed between the pivoted end of said arm and said relatively thinlug, whereby rotation of said bolt in one direction relative to saidlugs will spring said relatively thin lug toward said relatively thicklug to urge said looking washers into frictional engagement with saidarm for resisting swinging of the latter.

3. The combination according to claim 1, wherein the axis of said pivotmember is disposed in a plane substantially parallel to the plane ofrotation of the wheels so that said arm will swing in a plane at rightangles to said plane of rotation.

4. The combination according to claim 3, wherein said means resistingpivoting of said arm from the operative position includes a pair oftapered recesses formed in the opposite sides of said arm in the hookedfree end thereof, each of said recesses having its greatest depth at theend thereof closest to the free end of said arm and. being formed with awall at the end of greatest depth disposed at right angles to the planeof movement of said arm whereby a spoke received in one of said recesseswill engage against said wall thereof and prevent pivoting of said armfrom said operative position.

6 5. The combination according to claim 1, wherein said means on saidarm engaging one of said frame members and yieldably retaining said armin an inoperative position includesa longitudinally arcuate detentrecess formed in one side of said arm adjacent the free end thereof,said recess receiving said one of said frame members in said inoperativearm position.

6. A braking device for an invalids wheelchair having spoked wheels,opposite back-rest side frame members, and opposite arm-rest side framemembers; said braking device comprising a clamp adapted to be secured toone of said arm rest side-frame members, a pivot member on said clamphaving its axis in a plane substantially parallel to the plane ofrotation of said wheels and disposed outside of the periphery of thelatter, a locking arm swinging at one end on said pivot member andformed with a hooked free end loosely projecting axially between a pairof the spokes of the associated wheel when said arm is pivoted tooperative position, mean on said clamp frictionally resisting theswinging of said arm, means on said arm engageable with the Wheel spokesin said operative position for resisting swinging of said arm from saidoperative position, and means on said arm engageable with the adjacentone of said back-rest side frame members when said arm is in aninoperative position thereof and yieldably resisting movement of saidarm from said inoperative position.

RUTH A. CALDEIRA.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 200,856 Curren Mar. 5, 1878 1,414,756 ,Starck May 2, 19221,879,759 Mahr Sept. 27, 1932 2,284,220 Mandekic May 26, 1942 FOREIGNPATENTS Number Country Date 12,891 Great Britain May 26, 1914 230,314Great Britain Mar. 12, 1925

